Three Cool Things About AC
Your air conditioner is sort of like your phone or computer or the water that comes out of your faucet. It’s a modern convenience and you expect it to work. Except, sometimes it doesn’t. Which is when we start to feel helpless about our modern conveniences, especially when we don’t really know how they work.
It’s our belief that an educated customer is an air conditioning unit’s best friend. This blog details the following three things about air conditioners that you probably need to know:
- How an air conditioner works
- Reasons why an air conditioner fails
- Why you need to perform regular maintenance
How an Air Conditioner Works
Here’s a fun fact: did you know that your furnace and air conditioner are connected? Most people do not.
Your air conditioner uses the same blower fan motor as the furnace to move conditioned air throughout your home. It also uses the same control board to help communicate with your thermostat, helping to achieve your desired temperature. There are four main components of your HVAC system, furnace or air handler, outdoor condenser or heat pump, Indoor evaporator coil and duct work (delivery system).
As pointed out in How Stuff Works, “Air conditioners use refrigeration to chill indoor air, taking advantage of a remarkable physical law: When a liquid converts to a gas (in a process called phase conversion), it absorbs heat. Air conditioners exploit this feature of phase conversion by forcing special chemical compounds to evaporate and condense over and over again in a closed system of coils.”
A central heating and cooling system provides cool air through ductwork inside your home, with the help of the furnace or air handlers blower motor. This happens through a process that draws out the warm air inside and then removes its heat. What happens is the hot air flows over evaporator coils that contain liquid refrigerant, which absorbs the heat. The cooled air is then recirculated by being blown through ductwork that vents to all the rooms in your house.
When the refrigerant heats up, it turns into a gas. To convert the gas back into a liquid so it can absorb additional hot air, a compressor puts it under pressure. However, compressing the gas back into liquid form also creates additional heat, which must be evacuated outdoors with the help of a fan and a set of condenser coils.
This process continues again and again until your home reaches the cooling temperature you want, as programmed and sensed by your thermostat setting.
Well, even if you don’t get the physics of phase conversion where liquid refrigerant is converted to a gas that absorbs heat which is compressed back to a liquid to repeat the process, understand that an air conditioner is physically comprised of:
- Evaporator coils
- Air filter
- Condenser coils
- Condenser fan
So why would you need to know all this stuff? If you want to be sure your air conditioning system is working as efficiently as possible, this basic knowledge is necessary to understand why your air conditioning system can fail, and steps you can take to avoid that possibility.
Reasons Why Your Air Conditioner Can Fail
There are basically three things that could go wrong with an air conditioner:
1. Undersized Ductwork
Ducts inside your walls, crawl space and attic distribute conditioned air throughout your house. This system of ducts is collectively known as duct work. Undersized and inadequately distributed ductwork can cause uncomfortable spots in your home, uneven airflow and restrictions on your HVAC system.
Think of your heating and cooling system as your heart and the duct work as your veins and arteries. If your heart is fully functional and in good health, what happens to it when the arteries and veins of your circulatory system are clogged?
Right, your air conditioning system could have a heart attack or other underlining premature health (or failure) issues.
Your heating and cooling system share the same ductwork. Cooled conditioned air is denser than heated air, so it needs larger ductwork to adequately deliver it. If your ductwork system was designed primarily to convey heated air, as is the case when an old furnace is upgraded to add air conditioning, you may experience higher utility costs and uncomfortable spots in your home due to insufficient circulation of conditioned air. It can also lead to premature failure of the system.
Want to be sure your ductwork is properly sized? Flow hood tests can be performed to find out how much airflow is coming into your home compared to how much airflow your system should and could produce. This test will also tell you how much air, calculated in CFM (Cubic Feet Per Minute) is required to heat or cool a room correctly based on the square footage and heat load. Consult a qualified heating and cooling expert to perform these tests.
2. Refrigeration Leaks
Most people think that they need to recharge their air conditioning system every few years just as they do the air conditioning in their cars to ensure it is running as efficiently as possible. However, a car air conditioning system is not the same as a house air conditioner.
Unlike cars where road vibration can occasionally create small leaks within the refrigeration system, thus requiring potential recharging, your home air conditioning system is a closed circuit in a stable environment. Consequently, it doesn’t need recharging over its lifespan as long as it was properly charged when a licensed professional installed it.
If you feel as if your air conditioner is not working efficiently, you need a licensed professional to inspect it. It could be there is a leak somewhere in the system. This could be caused by:
- A very small leak incurred during the original installation
- The system was never properly charged from the original installation
- An aging indoor coil or outdoor condenser developed a small leak
- Work done around the air conditioning unit accidentally damaged the refrigeration line
3. Lack of Maintenance and Cleaning
Keeping your outdoor coil cleaned can help with the efficiency of your condenser. This is something any homeowner can perform carefully with a hose to avoid damage. There is also an indoor evaporator coil that over time can collect dirt, pet hair and other debris. Also, filtration that is clogged and or has not been changed in a while, could also cause immediate and permanent damage to your system. Anything that restricts airflow makes the air conditioner work inefficiently, possibly causing:
- Warmer temperatures indoors
- Refrigeration lines that freeze up, resulting in potential water damage
- A heavier workload for your HVAC system that over time shortens its working life
- Higher utility bills
To clean your indoor evaporator coil you will need to contact an HVAC professional to ensure it is done correctly. In many cases, however, homeowners can change their own air filters.
Perform Regular Maintenance
The best way to ensure your air conditioning is performing properly and at its most efficient is to perform regular maintenance. This encompasses:
- Change the air filter on a quarterly basis to ensure your heating and cooling system has a clean filter. Note: Some filtration systems, such as the Trane Clean Effects, only need to be cleaned or changed twice per year. Be sure to consult your HVAC provider on the type of filtration you have.
- Clean your outdoor coil with a lower pressure hose to ensure no dust and dirt build-up restricts any airflow needed.
- Remove bushes or other nearby debris near and around your outdoor condenser. Make sure you never leave anything on top of your condenser covering the fan. This can cause the compressor to fail within minutes if the restriction is significant.
- Have your system checked out at the start of every heating and cooling season by a professional certified technician to perform any necessary repairs or head off potential problems.
Regular maintenance ensures your system is working within manufacturer specifications and recommendations. Just like brakes or tires in your car, air conditioners have mechanical parts that over time can wear down and fail. The last thing you want is for your air conditioner to fail in the middle of a heatwave. Preventative maintenance helps prevent that possibility.
But, should it happen, rest assured Ongaro and Sons will respond quickly to address any emergency you and your air conditioner might experience.